Archive of posts by Richard Gilham
Why are plants green?
Friday, July 2nd, 2010
I guess there are two parts to the answer- why is green a good colour for plants to be, and how do they go about it. The key to the first part lies in how plants go about the business of living- they use light energy from the sun to drive the process of photosynthesis, which converts carbon dioxide into the sugars that they need to survive.
The fact that the leaves are green is because they are reflecting green light, and absorbing the other colours in the visible spectrum. When the light is absorbed, it is absorbed by the atoms that make up the leaves. These atoms, stuck together in molecules, gain energy from the light and this is needed to run photosynthesis. The reason plants decide to use visible light as opposed to infra-red or ultra-violet light is the same reason as why we see in the visible- there’s plenty of it around to use!
Posted in Featured, Your Questions | 4 Comments »
